Is there a way to setup captions with a script?

From the plug-in side: IID_ILINKCAPTIONPREFS has properties matching both groups of the dialog. E.g. from the bottom dialog group that are frame offset, paragraph style, layer and alignment.

The layer is stored by string, so don't rename the actual layer object after that.

The paragraph style is stored by ID.

There are "magic" strings such as "#CaptionSameLayerAsImage" and "#LinkInfoNameStr" - Rob, with your "Name" you eventually run into localization issues.

For the missing script properties I'd suggest you file a feature request via Uservoice.

Otherwise the approach by Rob looks ok. There is nothing special about the result from the generate caption menu action, poking around after the run will do.

Hi @wckdtall , I do it by invoking the Generate Live Caption menu item to script the caption generation—not sure if there is a better way. This example gets the parent frame of every placed link, invokes the menu, uses the file name for the caption, and styles the caption with paragraph and object styles:

app.doScript(makeCaptions, ScriptLanguage.JAVASCRIPT, undefined, UndoModes.ENTIRE_SCRIPT, 'Add Captions');

/**
* Make a Live Caption for every placed link 
*/
function makeCaptions(){
  app.scriptPreferences.measurementUnit = MeasurementUnits.POINTS;

  var d = app.activeDocument;
  var lnks = d.links.everyItem().getElements()
  for (var i = 0; i < lnks.length; i++){
    lnks[i].parent.parent.select();
    var makeCap =  app.menuActions.itemByName("Generate Live Caption")
    makeCap.invoke();
    setCaptionMeta("Name");
    setCaptionText(d.textFrames[0], 20, 5)
  };   
}
app.scriptPreferences.measurementUnit = AutoEnum.AUTO_VALUE;

/**
* Sets the caption’s metadata
* @ param the metadata name to use
* @ return void 
*/

function setCaptionMeta(n){
    
  var tv = app.activeDocument.textVariables
  for (var i = 0; i < tv.length; i++){
      try {
          var tvo = tv[i].variableOptions
          if (tvo.constructor.name == "CaptionMetadataVariablePreference") {
              tv[i].variableOptions.metadataProviderName = n
          } 
      }catch(e) {}  
  } 
}

/**
* Style the caption text frames 
* @ param the link’s parent frame
* @ param the caption height
* @ param the caption offset
* @ return void 
*/

function setCaptionText(tf, h, off){
  tf.select();
  
  var cStatic =  app.menuActions.itemByName("Convert to Static Caption");
  cStatic.invoke(); 

  var b = tf.geometricBounds;
  tf.geometricBounds = [b[0], b[1], b[0]+h, b[3]]; 
  tf.textFramePreferences.insetSpacing =  [off, 0, 0, 0];

  var ps = makeParaStyle(app.activeDocument, "Caption");
  ps.properties = {basedOn:"[No Paragraph Style]", appliedFont:"Myriad Pro	Regular", pointSize:8, leftIndent:0};
  tf.parentStory.appliedParagraphStyle = ps;  
  
  var ls = makeObjStyle(app.activeDocument, "Caption Frame");
  ls.properties = {basedOn:"[None]", appliedParagraphStyle:ps, strokeColor:"[None]", strokeWeight:"0"};
  tf.appliedObjectStyle = ls;  
}

/**
* Makes a new named ObjectStyle 
* @ param the document to add the style to 
* @ param style name 
* @ returns the new object style 
*/

function makeObjStyle(d, n){
  var os;
  try {
      d.objectStyles.add({name:n});
  }catch(e) {
      os = d.objectStyles.itemByName(n);
  } 
  return d.objectStyles.itemByName(n);
}

/**
* Makes a new named Paragraph Style 
* @ param the document to add the style to 
* @ param style name 
* @ returns the new paragraph style 
*/

function makeParaStyle(d, n){
  var ps;
  try {
      d.paragraphStyles.add({name:n});
  }catch(e) {
      ps = d.paragraphStyles.itemByName(n);
  } 
  return d.paragraphStyles.itemByName(n);
}

before and after:

> I always have a tough time figuring out where these things are in the model, 

You're not alone. . .

I had a look and indeed there's not a lot there. Not sure how to do what you want.

It probably can, but you'd have to give us a bit more info. Some screnshots of before and after situations would be useful.